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Aluminum Magnesium Boride (AlMgB14) also known as BAM is a material in the ultra-hard boride class. This material is characterized by its high hardness and resistance to friction and wear. BAM is among the hardest non-diamond materials. In particular, BAM with the addition of Titanium diboride (TiB2) gives the high hardness in all the ultra-hard borides.

Components
Aluminum magnesium boride (BAM) is also referred to as baseline for this kind of material. The baseline simply contains elemental aluminum, magnesium, and boron. The baseline will contain minimal impurity elements depending on its preparation. Additives that have been tested with baseline include: silicon, phosphorus, carbon, titanium diboride (TiB2), aluminum nitride (AlN), and boron nitride (BN).

Processing
The baseline material is produced by mechanically alloying the elemental materials. This provides a very fine powder. The finer the powder the better it will sinter during hot pressing and the better the elements will form with each other. The quality of baseline samples depends on the milling time, mill media, milling container geometry, atmosphere, and the type of milling that is performed. The powder is consolidated together using a hot press. The powder is placed into a graphite die while in an inert atmosphere to minimize oxygen content. Parts of the die are coated in with boron nitride to minimize adhesion to the die, so minor impurities could be present from this method. The most common temperature for this procedure is 1673K, which resulted in a 98% density of the theoretical 2.6g/cm3.

Hardness
BAM is different from most ultra-hard materials in that its structure is not very 	symmetric, the unit cell contains numerous atoms, and the unit cell is extremely complex. The 	unit cell is orthorhombic and is based off of four boron-containing icosahedra structures. Each 	icosahedra contains twelve boron atoms. Eight more boron atoms connect the icosahedral 	structures to the other elements in the unit cell. BAM is also outside of conformity from other 	ultra-hard materials, because it becomes increasingly harder when certain elements or 	compounds are added to the baseline. For instance, the hardest reading that researchers 	observed during one experiment included 30 wt% of the compound TiB2. Elemental additions 	such as silicon also increased the hardness up to about 35 GPa.

Coefficient of Thermal Expansion
The Coefficient of Thermal Expansion (COTE) for AlMgB14 was measured to be 9 x 10-6 K-1 by dilatometry and by high temperature X-ray diffraction using synchroton radiation. This value is very desirable for applications of AlMgB14 as a hard coating. The COTE of AlMgB14 is also close to a lot of highly used materials such as steel (11.7 x 10-6 K-1), titanium (8.6 x 10-6          K-1), and concrete (10-13 x 10-6 K-1). Based on the hardness values reported for AlMgB14 and the materials themselves being used as wear resistant coatings, the COTE of AlMgB14 could be used in determining coating application methods and the performance of the parts once in service.

Applications
BAM is not currently commercially available. BAM’s research is a continuing effort, but several applications have been proposed for the material. First, BAM could be applied as a coating to blades on pumps to reduce the friction between parts and increase wear resistance. The reduction in friction would also require less energy to consume. Another application is to apply the BAM coating to cutting tools. The reduced friction would again lower the force necessary to cut an object and extend tool life. The coating that would be necessary to observe such changes is only two to three microns thick.